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Jonathan_Healey
11-30-2007, 01:54 PM
I'm preparing a video presentation in a 32:9 (2880x810) aspect ratio for display at a conference. The conference center has a video wall with four, 50-inch plasmas running across (width) at two, 50-inch plasmas tall (height). They combine to make a 32:9 image. The conference centers plays movie files tot he plasmas from a PC running VLC.

I created a couple of samples for them and just returned from the test. My presentation is mostly white text on an orange backgroud. My first clip was exported using the DV-NTSC codec. At about 6-minutes it was about 1GB large. The video played well the edges of the text were pixelated. The type of pixelation you'll see on your computer screen in FCP but won't see on your broadcast monitor.

My second test used the Animation codec and ran about 2.7GB in size. This looks amazingly crisp however the Animation codec is not readable in VLC.

Any ideas how I can get crisp edges to appear on these plasmas within VLC and keep the file size below 3GB?

Arson
11-30-2007, 07:00 PM
dv ntsc is 720x480 so you are no where near the 2880x810 you want and that is why you see pixelation. You will probably notice that exporting as ntsc changed your footage from progressive to interlaced.

1 gig for 6 minutes sounds normal for ntsc and mostly white on orange (not alot of changing detail=better compression). Expect a file at the 2880 res to be quite a bit larger.

export as quicktime using animation codec (or photojpeg if you can handle the quality hit) the file sizes will be large, but you will maintain quality.
You can try h.264 compression if file sizes get too big

if you dont want to use Mov files export as an uncompressed AVI or to save space use divx or xvid. Both divx and xvid will show some compression though but you will save space.

Jonathan_Healey
12-01-2007, 12:24 PM
I merely used the DV-NTSC codec. Not it's usual pixel sixe of 720x480. It was export DV-NTSC at 2880x810.

milksac
12-01-2007, 02:18 PM
I did a quick test render out of AE. I was surprised that AE didn't present an error message when rendering out using the DV codec with the 2880 x 810 dimensions.
As arson said DV is 720 x 480. Anyway when I opened the file from the desktop it appeared very soft. Opening the movie info gave conflicting information; Format Apple DV 720 x 480, Normal size 2880 x 810. To my eye it looks like the image is being scaled up resulting in heavy artifacting. So I rendered out the same scene again using the H.264 codec - the image quality looked good and the file size was much smaller. Try rendering it out using the H.264 codec, it's compatible with VLC.

good luck. It sounds like an interesting project.

John Kary
12-02-2007, 07:30 AM
Arson, the problem with rendering to DivX/Xvid is that it's a third-party codec. If he doesn't play it from his machine, there's a possibility the other machine won't have the codec installed, and I don't think VLC plays DivX/Xvid without it.

Jonathan, you didn't say which OS the production machine has on it. If it's Windows (which it sounds like it is,) export from AE as a WMV. If it's OS X, export from AE as QuickTime. Both of those will accept an abnormal video size and not induce rescaling due to codec or format.

Arson
12-02-2007, 09:00 PM
Anything other than a "vanilla" avi you have no guarantees any machine will play it. Divx and xvid are now fairly ubiquitous. Even my 5 year old DVD player plays DivX DVDs.

Saving a file with those dimensions AND progressive frames as NTSC is changing the footage to interlaced and will cause a noticeable quality loss on playback on a progressive display. A computer monitor or LCD television are both progressive displays so you want to always maintain progressive footage instead of interlacing it.

Jonathan_Healey
12-03-2007, 08:27 AM
Jonathan, you didn't say which OS the production machine has on it. If it's Windows (which it sounds like it is,) export from AE as a WMV. If it's OS X, export from AE as QuickTime. Both of those will accept an abnormal video size and not induce rescaling due to codec or format.

It's a PC.

You can export from AE as .WMV? I'm unaware how to do that. I did try exporting my usual QT file and using Episode, Compressor and Squeeze to create .WMV files. All of which were stuttery upon playback.

Tin Man
12-03-2007, 09:51 AM
seems like a lot of work around to accommodate VLC at the convention center. wonder if they could just play on quicktime or any other avi player / dvd compatible format. I realize that you want to display you wares as the best quality possible so you may need to speak to tech about these issues and maybe find a player solution.

just my 2c

Tin Man

Jonathan_Healey
12-03-2007, 10:04 AM
I realize that you want to display you wares as the best quality possible so you may need to speak to tech about these issues and maybe find a player solution.



That would be the most logical thing - That is, ask them for their best practices; however, they've never had anyone use the screens in the this capacity so I'm on my own making tests. Usually, they'll take a clients DVD, footage, whatever and do a fit-to-fill technique. So someone will have their 4:3 or 16:9 image stretched. Frankly, it looks terrible. Other times, they'll double up two 4:3s next to each to fill the 32:9 screen.

I visited their "command center." Yes. QuickTime would be nice but for some reason they insist they can only use VLC on their PC. QuickTime, on their PC, doesn't have some sort of aspect ratio control (or something) to get it to fill the screen properly whereas VLC does.

In short, I'm working within the confines of what they've told me is available.

oneinfiniteloop
12-03-2007, 12:39 PM
I second using H264, or even QT PNG if it's supported.

Jonathan_Healey
12-06-2007, 09:22 AM
Thanks for all of the input. I ended up rendering with a 2880x810 aspect ration and used the DV-NTSC codec. It wasn't a sharp as I would have liked it but it served it's purpose and everyone was pleased.

joshtownsend
12-07-2007, 09:04 AM
My VLC player plays quicktime movies encoded with H264 rendered in after effects and I'm on a PC. There are some quicktime files VLC will play but H264 encoded ones work fine. VLC plays almost anything you throw out it. Pretty amazing little program actually.

milksac
12-07-2007, 12:31 PM
You can lead a horse to water. . .